What mfg are GM eproms? No metric essay content

[Programmer]

Heck of an idea--thanks for that one !!

Lyndon
-----Original Message-----
From: Robert W. Hughes <rwhughe at ev1.net>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Monday, June 07, 1999 11:31 AM
Subject: Re: What mfg are GM eproms? No metric essay content


>Some of the proms (TI is good about this) have the part number and
>manufacturer's name etched on the substrate. Use a 50 power microscope
>to look through the window and look around.
>
>Otherwise, to read the prom I just select generic 27512 and read it in. 
>If the data at $8000 is a repeat of the data at $0000 then it is a
>27256.
>If the data at $4000 is a repeat of the data at $0000 then it is a
>27128.
>If the data at $2000 is a repeat of the data at $0000 then it is a 2764.
>If the data at $1000 is a repeat of the data at $0000 then it is a 2732.
>
>Use the generic correct length chip selection at 12.5v to program. If
>there are a lot of errors, then use a higher voltage.
>
>Incidentally, plugging the prom into anything upside down will get you
>one little bright white flash in the window.
>-- 
>Robert W. Hughes (Bob)
>BackYard Engineering
>Houston, Texas
>rwhughe at ev1.net